Ship deck level sensor



July 963 v. s. KUPELIAN 3,097,565

SHIP DECK LEVEL SENSOR Filed Feb. 14, 1962 INV ENT OR 44 45 /46 Valley.5. Kupe/ian BY @35 W Mg ATTORNEYS United States Patent Ofifice3,097,565 Patented July 16, 1963 of the Navy m Filed Feb. 14, 1962, Ser.No. 173,311

7 Claims. (Cl. 891.7) (Granted under Title 35, US. Code (1952), sec.266) The invention described herein may be manufactured and used by orfor the Government of the United States of America for governmentalpurposes without the payment of any royalties thereon or therefor.

This invention relates to a sensing device and more particularly to alevel sensor for determining the level of the deck of a ship andproduces a signal when such a condition prevails.

More specifically the invention is particularly adapted for use with thelaunching equipment such, for example, as missile launchers wherein theequipment is not stabilized and thus it becomes necessary to initiateignition of the rockets therein when the deck of the ship is in a levelcondition.

The old method of determining deck level consisted of a visual operationsuch, as aligning the deck of the ship with the horizon by use of thenaked eye. This method has not proven to be entirely satisfactory sinceupon numerous occasions an unacceptable degree of deck level resulted.

Newer and more complicated devices and methods are based upon the use ofa conventional ships stable element which is the primary stabilizingsensor for the various guns and missile launchers on ships which are soequipped. The output from such a stable element is used to determine thevertical position but does not necessarily give a signal when the deckreaches a level position. This is due to the fact that the tolerancewithin the stable element is so delicate that a deck may oscillate for aconsiderable amount of time before it has achieved this degree of levelwithin its two axes of rotation. Consequently, if such a stable elementwere to be used for the purpose of determining deck level for rocketfiring, a considerable amount of time for leveling may be required aswell as resulting in much too fine a tolerance for the type of launchingfor which this device is intended.

The present invention is constructed and arranged to overcome all thedisadvantages encountered in prior art devices, and also provides asensing device which is responsive to the pitch and yaw of a ship andwhich oper ates to initiate a rocket or other ordnance device when thedeck of the ship reaches a level condition.

An object of the invention is to provide a sensing device forcontrolling the firing of a rocket from a launching rack or tube, as thecase may be.

Another object of the invention is to provide a deck level sensor whichproduces a firing signal when the deck of the ship is in a levelcondition.

A further object of the invention is to provide improved means forcontrolling the initiation of an ordnance missile.

A still further object of the invention is to provide an improvedsensing device wherein a movable element indicates a level position ofthe ships deck by casting a shadow on a photosensitive element therebyto produce a firing signal.

Still another object of the invention resides in the provision ofpendulum disposed between a source of light and a photosenstitiveelement and a firing circuit connected thereto and rendered effectiveaccording to the position of the pendulum with respect to thephotosensitive element.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes better understood byreference to the following detailed description when considered inconnection with the accompanying drawing wherein:

FIG. 1 is a pictorial view of a fragmentary portion of a shipillustrating a conventional missile launcher and the sensor of thepresent invention mounted on the deck thereof;

FIG. 2 is a view in perspective of the device of the present invention,partially broken away and partially in section; and

FIG. 3 is a diagrammatic illustration of the electrical circuit suitablefor use with the present invention.

The invention is herein illustrated as associated with a conventionalmissile launcher L mounted on the deck of a ship S and having a pair ofmissile launching arms A. The sensor of the present invention isindicated by the numeral 10. While the sensor 10 is shown mounted on themain deck D, it will be understood that the sensor may be mounted in anyconvenient place on the ship so that it is readily responsive to thepitch and yaw of the ship.

The sensor is constructed and arranged to determine the ship deck leveland to produce a signal for initiation of the missile so that themissile may be propelled from the launching arms A of the launcher L inthe conventional manner. The sensor, as illustrated in FIG. 2 comprisesa housing or casing 11 attached to a base 12 as by screws or the like 13and a gasket 14 providing a sealing connection between the casing andthe base 12. The casing 11 is further provided with a flange 15 :at theupper end thereof, which cooperates with a similar flange 16 formed on acover or dome 17. The aforesaid flanges 15 and 16 are secured by bolts18 and a gasket 19 provides a sealing connection therebetween.

A light source 21 is mounted on the end wall 22 of the cover 17 and apartition 23 carried by the cover is disposed in spaced relation withthe end wall 22 and is provided with a centrally disposed aperture 24.The partition 23 carries a plurality of supports 25 which extenddownwardly and inwardly and merge into a socket member 26 at the lowerend thereof.

A pendulum indicated generally by the reference character 27 is mountedin the socket 26 for oscillatory movement within the casing 11, thependulum including a rod or staff 28 having one end thereof mounted insocket 26, the other end thereof being provided with a weight or ball29. The movement of the pendulum is retarded or dampened by a quantityof viscous fluid 30 contained within the casing 11 of the sensor 10.

A partition 31 is carried by the casing 11 and is disposed in spacedrelation with respect to the base 12 and the partition 23. The partition31 is provided with a centrally disposed iris diaphragm 32 consisting ofthin opaque plates 33 carried by and adjustably mounted in a ring 34,the ring being rotatably mounted on partition 31 in any conventionalmanner thereby to adjust the aforesaid plates and vary the size of theaperture 35, if desired.

Mounted on the base 12 is a photosensitive cell 36, the cell beingcentrally disposed within the casing 11 in axial alignment with theaperture 35 in iris 32, the aperture 24 in partition 23, and lightsource 21 on end wall 22. The ball 29 on pendulum 27 also aligning withthe aforesaid components when the sensor is in a vertical position. Whenthe pendulum is in the aforesaid position the deck is in a levelcondition and the ball 29 on the pendulum interrupts the light rays fromthe light source 21, thus casting a shadow on the cell 36 whichactivates the cell. It will be understood that during the pitch and yawof the ship the pendulum is subjected to oscillatory movement, whereuponthe light rays from source 21 are projected 3 onto the cell and thus thecell is maintained in an inactive condition. From the foregoing it willbe further understood the pendulum indicates a level condition and alsoproduces a signal for activating an ordnance missile.

Referring now to FIG. 3 of the drawings, there is shown in diagrammaticform a circuit arrangement suitable for use with the sensing device ofthe present invention. Together with the light source 21 and thephotosensitive cell 36, the circuit further includes a battery B, arelay R and a conventional rocket initiator I usually mounted on thelaunching arms or tubes to cause initial operation or ignition of therocket.

It will be understood that the control or firing circuit 37, FIG. 3, forthe initiator I is normally open and will remain open until the deck ofthe ship is in a level condition and the normally activatedphotosensitive cell 36 is inactivated. When this occurs the pendulumball 29 casts a shadow on photosensitive cell 36 and thus the cell isinactivated, whereupon the cell is rendered non-conductive. from batteryB ceases to flow therethrough and thus the normally energized winding 38of sensitive relay R is deenergized. Upon de-energization of winding 38spring biased armature 40 of relay R moves from contact 39 intoengagement with make contact 39 thereof and thus the control or firingcircuit 37 to the initiator I is closed. When this occurs the initiatorI is rendered efiective and causes initial and instantaneous ignition ofthe conventional rocket motor or propellant, as the case may be. Currentis supplied to the source of light 21 from battery B by conductors 41controlled by a switch 42. A similar switch 43 may be used in thecontrol circuit 37 for preventing premature operation of the circuit,the control circuit including conductors 44, 45, 46, 47 and 48. From theforegoing, it will be apparent that a new and improved deck level sensorand system has been devised for firing rockets or ordnance devices fromshipboard, wherein the launching equipment is not stabilized, so thatinitial ignition or firing of the rockets or devices occur only when thedeck of the ship is in a level condition. be understood that by settingthe photosensitive cell to accept a certain threshold of light, thesensor of the present invention may be made to fail safe by requiringthe photosensitive cell to accept a certain amount of light fromactuation rather than a complete shadow, as heretofore set forth.Furthermore, by controlling the area of the light reaching thephotosensitive cell through the adjustable iris, the degree of decklevel can be preselected and by filling the casing with liquid thependulum process may be dampened or retarded to accommodateenvironmental extremes.

Obviously, many modifications and variations of the present inventionare possible in the light of the above teachings. It is, therefore, tobe understood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

What is claimed is:

1. A deck level sensor of the character described comprising a casingfixedly mounted on the deck of a ship and having a quantity of dampingfluid therein, a conical portion formed at one end of said casing andterminating in an end wall, a mounting flange carried by the casing atthe other end thereof, a first partition disposed within the casing inspaced relation with respect to said end wall, a second partitiondisposed within the casing in spaced relation with respect to saidflange, a window in said first partition, an adjustable iris in saidsecond partition, a source of light mounted on said end wall forprojecting light rays through said window and iris, an omni-directionalmovable body suspended from said first partition and disposed withinsaid fluid and actuated in response to the pitch and roll of the ship,and a photoelectric cell mounted on said flange and within the casingfor receiving said light rays according to the positions of said bodywith respect to the photoelectric cell As the cell is renderednon-conductive, current Moreover, it will 4 window and the iris and onlyduring the pitch and roll of the ship.

2. A sensing device of the character described comprising a casingfixedly mounted on the deck of a ship and having a quantity of dampingfluid, a conical portion formed at one end of said casing andterminating in an end wall, a mounting flange carried at the other endof the casing, a first partition disposed within the casing in spacedrelation with respect to said end wall, a second partition disposedwithin the casing in spaced relation with respect to said flange, awindow in said first partition, an adjustable iris in said secondpartition, a source of light mounted on said end wall in spaced relationwith respect to said first partition for projecting light rays throughsaid window and the iris, an omni-directional movable support carried bythe first partition, a pendulum mounted on said support and disposedw'ithin said fluid and actuated in response to the pitch and roll of theship for omni-directional movement, and a photoelectric cell mounted onsaid flange and within the casing for receiving said light rays onlyduring omni directional movement of the pendulum and according to theposition of said pendulum with respect to the photoelectric cell, windowand iris.

3. A sensing device of the character described comprising a casingfixedly mounted on the deck of a ship, a window disposed within saidcasing, an adjustable iris disposed within said casing and aligned withsaid window, a source of light within the casing for projecting lightrays through said window and iris, a photosensitive cell mounted withinthe casing and activated by said light rays as the light rays areprojected through said window and the iris, an omni-directional movablependulum mounted within the casing and actuated in response to the pitchand roll of the ship, said pendulum casting a shadow onto thephotosensitive cell through said iris only when the deck of the ship isin a level condition, the pendulum is in axial alignment with thewindow, iris and photoelectric cell and the casing is in a verticalposition thereby to inactivate the photosensitive cell, and a quantityof fluid within the casing and surrounding the pendulum for retardingthe movement thereof.

4. In a level sensing device fixedly mounted on the deck of a ship forproducing a rocket firing signal when the deck of the ship is in a levelcondition, a light sensitive cell rendered ineiiective as a shadow iscast thereon, means for projecting light onto said light sensitive cell,an omni-directional movable pendulum responsive to the pitch and roll ofthe ship for interrupting said light and casting said shadow onto thelight sensitive cell to inactivate the cell and produce said firingsignal only when the deck of the ship is in said level condition and thependulum is in axial alignment with the light sensitive cell, and meansincluding a firing circuit for receiving said firing signal when thecell is inactivated thereby to initiate ignition of the rocket.

5. In a level sensing device adapted to be fixedly mounted on the deckof a ship for producing a rocket firing signal when the deck is in alevel condition, a light sensitive cell rendered ineffective as a shadowis cast thereon, a light source for projecting light onto said lightsensitive cell, an omni-directional movable pendulum responsive to thepitch and roll of the ship for interrupting the light projected onto thecell and casting a shadow thereon to inactivate the cell only when thependulum is in axial alignment with the source of light and the cell andthe deck of the ship is in a level condition, the inactivation of thecell producing said firing signal, a rocket initiator for initiatingignition of the rocket as the firing signal is received thereby, andmeans operated as said cell is inactivated for transmitting the firingsignal to said initiator.

6. In a system for initiating ignition of a missile supported on amissile launcher mounted on the deck of a ship when the deck is in alevel condition, the combination of a normally open control circuit, acontrol relay for closing said circuit as the relay is operated, a lightsensitive cell rendered effective to operate said relay when the lightrays projected thereon are interrupted, a source of light for projectinglight rays onto said light sensitive cell, an omni-directional movablependulum responsive to the pitch and roll of the ship for interruptingsaid light rays only when the pendulum is in axial alignment with saidcell and the source of light and the deck of the ship is in said levelcondition, a missile initiator included in said circuit for receivinginitiating signal when the relay is closed thereby to initiate ignitionof the missile, and a source of electrical energy in said circuit forsupplying electrical energy to said initiator when the circuit isclosed.

7. An apparatus for initiating ignition of a missile comprising a casingfixedly mounted on the deck of a ship, a light source and aphoto-sensitive cell disposed within the casing, said light sourceprojecting light onto said photosensitive cell to activate said cell,said cell being inac- 6 tivated when said light is interrupted,omni-directional movable means responsive to the pitch and roll of theship and disposed between the light source and the cell for interruptingthe light only when the movable means is in axial alignment with thelight source and the cell and the deck of the ship is in a levelcondition, and means including a relay operated when the cell isinactivated for initiating ignition of the missile.

References Cited in the file of this patent UNITED STATES PATENTS1,452,484 Sperry Apr. 17, 1923 2,131,028 Goodsell Sept. 27, 19382,236,543 McFaddan Apr. 11, 1941 2,450,551 Harrington Oct. 5, 19482,498,997 McLean et a1. Feb. 28, 1950 2,665,896 Kirby et .al Jan. 12,1954 2,919,583 Parker Jan. 5, 1960 2,995,935 Eyestone et al. Aug. 5,1961

4. IN A LEVEL SENSING DEVICE FIXEDLY MOUNTED ON THE DECK OF A SHIP FORPRODUCING A ROCKET FIRING SIGNAL WHEN THE DECK OF THE SHIP IS IN A LEVELCONDITION, A LIGHT SENSITIVE CELL RENDERED INEFFECTIVE AS A SHADOW ISCAST THEREON, MEANS FOR PROJECTING LIGHT ONTO SAID LIGHT SENSITIVE CELL,AN OMNI-DIRECTIONAL MOVABLE PENDULUM RESPONSIVE TO THE PITCH AND ROLL OFTHE SHIP FOR INTERRUPTING SAID LIGHT AND CASTING SAID SHADOW ONTO THELIGHT SENSITIVE CELL TO INACTIVATE THE CELL AND PRODUCE SAID FIRINGSIGNAL ONLY WHEN THE DECK OF THE SHIP IS IN SAID LEVEL CONDITION AND THEPENDULUM S IN AXIAL ALIGNMENT WITH THE LIGHT SENSI-